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Greater Seattle Aquarium Society

Tales from the Krib

the Saga of My Continuing Attempts to Breed Pelvicachromis pulcher

by Dr. Erik Olson
Greater Seattle Aquarium Society Newsletter, March 1995

[Note: This article won the 1995 Greater Seattle Aquarium Society Disaster Contest. I am not sure whether to be proud or ashamed. - EO]

I haven’t tried breeding too many fish... Usually for me they’re in my tanks to add a little color to the plants. :) But for some reason, I’ve been almost fixated on breeding the common Kribensis or Pelvicachromis pulcher. Partly this has been due to what seemed like a curse on my ability to keep these simple fish long enough to identify their sex (much of this article is an entry in the Great Disasters contest). Take a look at how it unfolded in my fish log book, and keep track of the death count!

August 1992
Purchased a pair of 1-inch Kribs for my community tank. They’re completely indistinguishable, though the store guy said he picked the shortest, fattest one, and the longest skinniest one, and said using this method there’s a 95\% probability that they’ll be a pair.
September 1992
After returning from a 1-month business trip, both are nowhere to be found (2), though the other fish are OK.
January 1993
Back to the store for another tiny pair. The employee that day says to sex them you look at the color strip along its dorsal fin; if it extends all the way to the tail, it’s male, but in females it becomes clear before the end. Of course, these specimens are too small to tell for sure. During the innagural day storm and power outage both are killed (4).
February
After pouring through every picture I can find, I decide rounded pink belly indicates female and pointy dorsal fin indicates male, and this time buy a couple of 2-inchers. Putting them in a 10-gallon tank turns out to be too much for the smaller of the two; it is killed (5) by the other, who we subsequently name Paaat from its indeterminate sex. After two months, it gets pop-eye and expires (6).
May
Returning to small fish again, I quarantine another pair in a 10 gallon tank. Tragically, a clay pot of unknown origin (purchased from some sort of aquarium auction thingy) releases a mysterious toxin is into the water and extinguishes all animal (8) and most plant life in the tank. (Kids, always use new pots; they’re cheap.)
October
Some really nice-looking Kribs are on sale, so I decide to try again. The store guy thinks they’re all male, and he’s right: They’re skinny. They have pointy dorsal fins. They have color running all the way back. But they also have pink bellies occasionally.

At this point it’s worth saying I figured out what a pair looks like. The key is definitely that dorsal fin color and shape, and the red belly nothing more than a red herring (ho ho). There are other secondary signs, like the pointy anal and dorsal fins on the males, but the color trick is almost guaranteed to work every time. Since I was now knee-deep in full-grown males, the next task was finding an adult female and keeping her alive.

October 1993
I find a real pair in another store. They’re large and much prettier than any of the previous ones, the male having several eye-spots on its caudal fin. [I’ve seen a wide variety in the markings and coloration, from orange vs. blue fin tips, to number of eye spots on dorsal and caudal fins; they’re all the same species.] The male immediately moves into an overturned clay pot (a non poison-injected type). The female refuses to eat, and dies a week later (9). Now I have three males in perfect health, rapidly forming a caste system where the large male beats up on the smaller two.
27 January 1994
A fellow society member gives me a true female. She doesn’t eat much & hides most of the time, but seems healthy. Gradually she comes out a bit more, mostly to hang out with one of the small males, but still gets the leavings of the food. I find myself cheering whenever she gets a flake.
12 February
To keep them interested in breeding instead of fighting, one small male is donated to a fish store. I don’t have the heart to part with the big male. Maybe I’ll find him a larger female companion later. Meanwhile, the remaining small male and the female are hanging around together almost exclusively.
2 March
The female digs a small cave under the bogwood root. She chases everyone else out of the area except for the small male.
5 March
The male and female are now jointly beating up on the big male by tag-team nipping him out of their new territory.

Finally! Success! I decided to not interfere with the parents, and see what would happen on their own against the formidable Congo Tetras and various bottom feeders, not to mention the other male...

8 March
Came home and couldn’t find the female when feeding the rest. On closer examination I found her under the plants guarding a wriggling mass of speckled fry. Looks like about a dozen or so. Parts of the egg can still be seen as a glob on their stomach. The male seems to be providing help fighting off other fish.
9 March
They’re bigger already.
10 March
The family now hangs around the bogwood and plants several inches off the gravel. The parents seem to switch off care, like Mom will dash off to eat while Dad watches the kids. If both parents take off, the young press themselves against the gravel or wood.
11 March
I now count about 15-18 young. I can see green in their stomachs from the algae they’re eating. Eyes, orange-ish, now visible. Maybe 5-7mm long. Is their speckled pattern special to my gravel? They really camoflauge into it. It is impossible to uproot and clean any plants because the pair keeps attacking my hand.
15 March
I can now see dorsal fins on the fry. There are about ten remaining.
22 March
No sign of the fry anymore. Have they been eaten by the other fish or their parents?

Well, Next I made a mistake. I should have left the happy couple alone, maybe removed the other male. But instead I got cocky...

21 April
In an attempt to make the big male happier, I find a second female. Initially, she seems to warm up to the male by hanging out in his cave...
27 May
...but instead kills the smaller female (10), and then mysteriously dies herself (11).
25 June
The large male dies (12).

Oh well... back to the drawing board with the one male left. After a summer break, it was time to try again!

August
I take a new tack, and get rid of the competition, namely congo tetras and barbs. I also find yet another female, but am worried since she’s only about 1" (while the male is easily three times that size).
September
The male chases the small female a lot, but she is feisty and clever! She hides in the plants instead of being backed into a corner. Her colors are also becoming quite vivid.
5 October
Returning from a trip to uproot plants, I think I’m getting an electric shock from my undergravel heating coils, but it turns out to be that male attacking my knuckles! Oh boy!
11 October
Sure enough, they’re guarding a brood of about 20 fry. They shuffle them around to different areas of the tank to forage for food, just like the other spawning. Since the other fish population is far smaller now, maybe they’ll have a chance?
18 October
No, the fry have now all disappeared again. But... The parents are showing colors again, and the female is doing the shimmy dance, so they may get another chance this month.
8 November
The male’s attacking me again when I clean, and the female seems to be guarding a clay pot. Can’t see eggs, even when I poke around with a flashlight.
12 November
Yes! Another batch of free-swimming fry being led around by mom & pop. I have an empty tank, so I try an experiment and siphon out about 20 fry. But still there’s 30-40 still left! Guess they’re becoming better parents.
14 November
I’m going to try some baby brine shrimp this time. I dumped 1-1/2 tbsp of uniodized salt, 3 pints of water, an airstone and a cheap heater into an orange juice pitcher and let it bubble away at 85 degrees.
15 November
That was easy! Not sure why I had trouble with hatching brine shrimp before, but it might be that I missed the heater part. Anyway, I’m dumping some in 3 times today before starting a new batch. The fry love it -- they’ve got bulging pink bellies. Meanwhile, another difference with the parents: Dad spends most of his time guarding the fry, and mom does perimeter guarding and gets first crack at the food. Even if the fry don’t survive, I’m betting the parents live this time.
November 19
Alive and growing... The ones left with their parents are noticably bigger and more active than those I separated the first day. I’ve now perfected the brine shrimp gun, siphoning the baby Artemia out of a cup and aiming them into the tank, directly at the fry. The parents don’t even attack the tube anymore.
December 5
Took another load of 12 out of the main tank last week; now there’s 18 under adult supervision, and 18 on their own in the other tank. Since they’re now 7mm long, I stopped feeding baby brine and they now eat the flake food leavings from the normal feeding. At one point, Mom looked like she was swallowing one, but it wouldn’t fit in her mouth. Recently, Dad was showing off the whole bunch to me in a parade around the front glass; I think I’ve finally succeeded!

Appendix: It is now mid-July 1995, and both parents are still alive and have produced spawns almost every month. My tank has a fairly low pH due to the CO2 injection; perhaps this is why I’ve gotten a total of one male out of the 15-20 matured offspring to date. I think I’m ready to try something more advanced... maybe black mollys. :)